You are here:

Health Library

Blood Pressure Numbers: When to Get Help

Topic Overview

If you check your blood pressure, you may wonder when an abnormal reading means you should call your doctor. This information can help you understand what your blood pressure numbers mean and when you need to call for help.

What do blood pressure numbers mean?

Your blood pressure consists of two numbers: systolic and diastolic. Someone with a systolic pressure of 117 and a diastolic pressure of 78 has a blood pressure of 117/78, or "117 over 78."

An ideal blood pressure for an adult is less than 120/80 ("120 over 80").

In general, the lower your blood pressure, the better. For example, a blood pressure reading of less than 90/60 is healthy as long as you feel okay.

What can cause a short-term change in blood pressure?

It's normal for blood pressure to go up and down throughout the day. Things like exercise, stress, and sleeping can affect your blood pressure. Some medicines can cause a spike in blood pressure, including certain asthma medicines and cold remedies.

A low blood pressure reading can be caused by many things, including some medicines, a severe allergic reaction, or an infection. Another cause is dehydration, which is when your body loses too much fluid.

When should you get help for an abnormal blood pressure reading?

One high or low blood pressure reading by itself may not mean you need to call for help. If you take your blood pressure and it is out of the normal range, wait a few minutes and take it again. If it's still high or low, use the following guidance.

This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.